Carbonizing oven having parallel horizontal flues and u-shaped air ducts



July 7, i970 M. D. CURRAN 3,519,540

CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTSFiled May 6. 1968 6 Sheets-Sheet 2 FIG. 3

INVENTOR MAURICE D. CURRAN ATTORNEY .uy 7 E? M. D. CURRAN 3,519,549

CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTSN m ,v Q LL.

Q QM Y INVENTOR MAURICE D. CURRAN BY wwjd ATTO RNEY uy 7, CARBONIZINGovLN HAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS 6Sheets-.Sheet 4 Filed May 6. 1968 RlmmlWHllwMA-l t..

L MAURICE D. CURRAN BY @LA fi @im 6 9 S Juiy 7, ff M. D. RRAN 3,519,540

' CARBONZING OVEN HAVING P LLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTSFiled May 6, 1968 6 Sheets-Sheet 5 i Si; i

\ GAS LINE m j AIR LINE 52 L iig-TURN cojvEvoR 53 k`\ INVENTOR I MAURICED. CURRAN Bv @n ATTORNEY Juy 7, 1970 M. D. CURRAN CARBONIZING OVENHAVING PARALLEL HORIZONTAL FLUES AND U-SHAPED AIR DUCTS 6 Sheets-Sheet 6Filed May 6. 1968 :ll- IIIIIZII' INVENTOR' MAURICE D CURRAN ATTORNEYUnited States Patent O CARBONIZING OVEN HAVING PARALLEL HORIZONTAL FLUESAND U-SHAPED AIR DUCTS Maurice D. Curran, 916 Davis St., Garden City,Kans. 67846 Filed May 6, 1968, Ser. No. 726,751 Int. Cl. Cb l/06 U.S.Cl. 202-117 7 Claims ABSTRACT OF THE DISCLOSURE A carbonizing ovencomprising a refractory chamber and a lower chamber, the floor of saidrefractory chamber being fabricated of material having heat transferproperties and a conveyor for pushing waste organic material along saidrefractory chamber floor for direct subjection to heat passingtherethrough. Heat producing means are located `between said upper andlower chambers and consist of air ducts and combustion lines arranged inpaired, vertically aligned relationship for extension transversely ofthe oven and with said ducts being suitably connected to exteriorsupplies of air and gas.

BACKGROUND AND SUMMA'RY OF THE INVENTION This invention relates ingeneral to carbonization of waste and, more particularly, to an ovenadapted for effecting such carbonization. Heretofore, such procedures ashave been used for reducing carbon from Waste material have beenconsistently of batch character, requiring the subjection of apredetermined quantity of raw material to the particular sequence oftreatment steps before the next batch is charged. Consequently, theproduction of such carbon has been relatively expensive and has as Wellrequired utilization of rather complex equipment.

Therefore, it is an object of the present invention to provide acarbonizing oven which is adapted for continuois operation, thus,obviating the heretofore accepted batch operation and to be productiveof substantial econ` omies is operation.

=It is a further object of the present invention to provide acarbonizing oven which incorporates means for moving raw materialdirectly across a heat transfer surface as contradistinguished fromsystems involving the use of receptacle-type conveyors whereby the rawmaterial is subjected to heat directed from above rather than below.

It is another object of the present invention to provide a. carbonizingoven which is uniquely adapted to utilize as a fuel gas produced as aby-product from the distillation of the raw material thereby furtherconducing to economy in operation.

It is a still further object of the present invention to provide acarbonizing oven of the type stated which requires the minimum inpersonnel for operation.

It is an further object of the present invention to provide an oven ofthe type stated which may be economically constructed; which is durableand reliable in usage; and the use of which will allow for the rapid,high volume, relatively cheap production of carbon.

BRI-EF DESCRIPTION OF THE DRAWINGS FIG. l is a top plan view of acarbonizing oven constructed in accordance with and embodying thepresent invention.

FIG. 2 is a fragmentary vertical transverse sectional view taken alongthe line 2 2 of FIG. 1.

FIG. 3 is a vertical transverse sectional view taken on the line 3 3 ofFIG. l2.

FIG. 4 is a horizontal transverse sectional view taken on the line 4 -4of FIG. 2.

FIG. 5 is a vertical transverse sectional view taken on the line 5 5 ofFIG. 3.

FIG. 6 is a top plan view of the upper course of the conveyor.

FIG. 7 is a side view taken on the line 7 7 of FIG. 6.

FIG. 8 is a schematic vertical transverse sectional view takensubstantially on the line 3 3 of FIG. 2 for illustrating the operationof the oven.

FIG. 9 is a vertical transverse sectional view taken substantially onthe line 4 4 of FIG. 2 illustrating another flue arrangement constructedin accordance with and embodying the present invention.

FIG. l0 is a vertical transverse sectional view taken substantially onthe line 5 5 of FIG. 3 but illustrating the flue arrangement shown inFIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now by referencecharacters to the drawings which illustrate the preferred embodiment ofthe present invention. A generally designates a carbonizing oven, asindicated in FIG. l, which is of substantial elongate characterincorporating a framework, as at F, of I-beams and like structuralcomponents for maintaining the integrity of oven A by buttressing theside walls S, s thereof, said latter being desirably basically of brick.Oven A and framework F are supported upon a concrete foundation C; therebeing preferably several layers of Ventilating bricks 1 between saidfoundation C and base wall 2 of oven A. Supported upon the upper ends ofside walls s, s is a top wall 3 which may be of concrete, brick, orcombinations of the same. Extending substantially the length of oven Aare lower and upper vertically spacedapart tunnel-like chambers 4, 5respectively; the ends of said chambers terminating in immediatelyspaced relationship to oven end walls, as indicated at 6 (FIG. 7) and 7(FIG. 2). Upper chamber 5 is of refractory character comprising an upperarch wall 8, parallel side walls 9, 10, which are integrated with theadjacent oven side walls s, s', respectively, and a floor 11; whichcomponents are continuous throughout their length thereby leavingchamber 5 open at its extreme ends. Floor 11 is fabricated, by choice,of silica brick for conducing to heat transfer, while side Walls 9, 10are formed of lire brick and arch wall 8 is preferably of fire clay.

Lower chamber 4 is of generally like design as upper chamber 5 andcomprises an upper arch wall 12 located spacedly downwardly of floor 11,side walls 13, 14, as constructed preferably of brick, with the iloor ofsaid chamber being constituted of oven base Wall 2. As is evident fromFIG. 3, chambers 4, 5 may be of substantially like dimensions andvolume.

Mounted within oven A proximate each end 6, 7 immediately beyond theends of chambers 4, 5 and disposed for rotation about an axis extendingtransversely between side walls s, s are transversely aligned pairedsprocket wheels 15, 15', 16, 16', respectively. Sprocket wheels 15, 15'are mounted upon a shaft 17 projecting through suitable apertures inside walls s, s' for journaling within bearings 18, 18 providedexternally of said side walls. Shaft 17 extends beyond bearing 18 foroperative connection to a gear reducer 19 which is suitably connected toa prime mover 20. Sprocket wheels 16, 16 are mounted upon an idler shaft21 which, at its ends, projects through openings in side walls s, s' forjournaling within exteriorly provided bearings 22, 22'. Trained aboutsprocket Wheels 15, 16 and 15', 16 are the chains 23, 23', respectively,of an endless conveyor, designated generally E; there being push bars 24extending transversely between said chains 23, 23 at spaced intervalsthroughout the entire extent thereof; said push bars 24 beingpreferably, but not necessarily, of angle shape having a vertical leg 25and a relatively shallow horizontal leg 26, which latter, on their undersurface, will travel contactingly across the upper face of floor 11 ofupper chamber 5. Thus, as is indicated in FIGS. 2 and 7, the uppercourse `of conveyor E travels through upper charnber 5 in a directiontoward end Wall 7 so that said upper course may be considered the loadconveyor, while the lower course of conveyor E moves through lowerchamber 4 on steel rails in a direction toward end wall 6 with suchcourse being considered the return conveyor. Thus, push bars 24 aremutually spaced for impelling material, of the type to be describedhereinbelow, through upper chamber 5 by travel across floor 11.

As indicated in FIG. 7, oven A is provided with a suitable opening 27 intop wall 3 proximate end wall 6 for charging raw material to the uppercourse of conveyor E. Continuous with floor 11 at its end proximate endwall 7 (see FIG. 2) is a downwardly directed chutelike guide 28 fordirecting the now-treated material for delivery by gravity to a hopper29 located therebelow; there being associated with said hopper aconventional screw conveyor, as broadly indicated at 30, for removal ofthe treated material to a suitable collection point beyond oven A. Abovehopper 29 there is presented a pipe 31 connected to a suitable source ofWater for directing quenching water into said hopper 29 for cooling theheated materials. In view of the foregoing, it will thus be seen thatoven A is uniquely adapted for continuous operation whereby raw materialcharged to conveyor E at one end of oven A is suitably treated by asingle pass through upper chamber 5 and with the treated material beingeffectively discharged as promptly as delivered. Accordingly, oven Ao'bviates the heretofore time-consuming, costly batch operations asaccepted in carbonizing procedures.

Provided above arch wall 12 of lower chamber 4 is a partition 32, as offire brick, extending transversely between sides s, s'. Upon the uppersurface of partition 32 is disposed a multiplicity of ducts 33 which arespacedapart longitudinally of oven A and extend transversely betweensides s, s. Said ducts 33 are similarly formed of re brick or likematerial. Provided above ducts 32 is a series of combustion ilues 34,being similarly spaced-apart longitudinally of oven A for extensiontransversely thereof. Said fiues 34 are defined by structural portionsformed of silica or the like and with the upper component of said ues 34being constituted by floor 11 of upper chamber 5 for ready heat movementtherethrough from the cornbustion within said llues 34. Ducts 33 areclosed at one of their ends, as by wall s or s as the case may be, andat their opposite ends are in communication with air inlet pipes 35extending through an opening 36 formed in the associated side wall s, s.Air inlet pipes 35, outwardly of the adjacent wall of oven A, areconnected through a manifold 37 which, in turn, communicates through anair supply pipe 38 with a convenient air supply, as indicated at 39 inFIG. 8.

Referring now to FIG. 4, it will be observed that the air inlet pipes 35are arranged in groups or banks, as suggested at 40 in FIG. 1, which arelocated upon opposite sides of oven A and, thus, are staggered oralternated throughout the length thereof. It is to be recognized thatthe number of air inlet pipes in any one bank may be determined byconsideration of numerous, obvious factors.

Each flue 34, at One of its ends, is closed, as by wall s or s', and atits other end is continuous with a gas inlet pipe 41, which is securelyreceived within opening 42 formed in the related side wall s, s', as thecase may be. At their outer ends, gas inlet pipes 41 are connected to amanifold 43. In turn, the gas manifolds 43 are connected to a gas supplypipe 44 (FIG. 8) Which leads from a convenient gas supply, designated45. Referring to FIG. 4, it will be seen that gas inlet pipes 41 arearranged in groups or banks which, perforce, correspond in number to theair inlet pipes 5 co-ordinating therewith. Said banks or groups of saidgas inlet pipes 41 are indicated at 46 in FIG. l and, thus, said banksor groups will alternate or be staggered throughout the length of ovenA. As may be apparent from FIG. 4, the number of gas inlet pipes 41 inany one bank, and the number of air inlet pipes in any one bank, areshown as being nine in number since each air duct 33 will be in paired,co-ordinated relationship with a gas flue 34. It is also apparent thatgas and air pipes 41, 35 respectively, are provided with orifice controlplates, as indicated generally at 47, 48, respectively, for controllingthe relative amounts of gas and air in each flue 34.

Each air duct 33 in its end portion remote from its related inlet pipe35 and in its upper wall, is provided with a port 49 which is located inimmediate proximate relationship to the inner end of the related gasinlet pipe 41 for effecting combustion, with heat being developedthroughout ue 34 for transfer through oor 11 for treatment of the rawmaterial being conveyed therethrough by conveyor E. Flues 34, in theirend portions remote from the respective gas inlet pipe 41, are incommunication with a passage 50 through partition 32 for communicatingwith the volume between the latter and the upper surface of arch Wall 12of lower chamber 4, such volume or compartment being indicated at 51.Provided along the side of volume 51, beneath each bank of gas inletpipes 46, is the upper end of a plurality of ducts 52 which extendoutwardly of the related Wall for communication at its other end with awaste gas flue 53 which may be incorpOrated in foundation C.

Arch wall 8 of upper chamber 5 is provided spacedly along its length,and substantially transversely thereof, with a plurality of openings 54for receiving ttingly therein the lower ends of upstanding collectorpipes 55; the upper ends of the latter project through openings 56 intop wall 3 for extension thereabove, as at 57. Said collector pipes 55,at their upper ends, are continuous with a horizontal conduit 58 forcommunication through the latter with an elongate gas collecting main ortrap 59. Trap 59 is connected to a gas purifier or scrubber 60 (FIG. 8)wherein gas within the gaseous waste from matter being treated inchamber 5 is separated from water and other inpurities therein entrainedso that the gas emitted from scrubber 60 may be directed to gas supply45 by a gas exhauster for ultimate usage as fuel within the combustionsystem of oven A.

Oven A is especially designed for carbonizing organic waste matter, suchas, for instance, wood, vegetable matter, and the like. Such matter maybe obtained from any source of refuse, as, for instance, a city dump,but it is understood that all metallic, ceramic, glass, and rubber willbe separated prior to charging of the raw material to oven A. Such rawmaterial is thus directed upon oor 11 of chamber 5, at the proximate endwall 6, for travel therealong through operation of the push-bar conveyorE as above described. Said raw material is thus in immediate Contactwith the heat transfer surface deiined by oor 11 through which, as abovedescribed, heat is passing from combustion ues 34. It is to be observedthat air being directed from air supply 39 to air inlet pipes 35 is notpre-heated but is at a slight controlled pressure, such as in the orderof 2 mm. of Water pressure as required to provide a balanced pressure inilues 34. During travel of air through ducts 33 toward port 49,preheating will occur by reason of transfer from ilues 34. Thetemperature developed within combustion tlues 34 is appropiatelycontrolled to be within the range of about 1000-l400 F. for effectivelycarbonizing the organic raw material. Obviously, oven A is adapted t0operate at a temperature below that wherein push bars 24 of conveyor Ewould tend to weaken.

The products of distillation in gaseous form, from the carbonizing ofthe raw material, will be directed upwardly through collector pipes 55for ultimate separation in scrubber 60. Thus, the by-products of the rawmaterial will enhance the economy of operation of oven A by constitutinga continuing source of fuel. As described above, the treated rawmaterial, which is now carbon, will be deposited in hopper 29 for anyfurther treatment as might be indicated, such as, for instance, for theproduction of activated carbon, for the manufacture of briquettes forfuel purposes etc.

Any waste fuel gas within lower chamber 4 may be dissipated to theatmosphere through a conventional chimney (not shown).

Referring now to FIGS. '9 and l0, there is illustrated another system ofgas and -air provision for oven A. Immediately provided above partition32 is a plurality of generally U-shaped air ducts 61 each having a pairof legs 62, 63 in axially parallel relationship, extending transrverselyof oven A and being connected at one of their ends by -a short section64. Each leg -62 of each duct 61, is connected at its end oppositesection 64 to an air inlet pipe 65, which latter is suitably fixedwithin an opening 66 in wall s of oven A. Each of said pipes 65communicate at their outer ends with a continuous air manifold 67located immediately outwardly of wall s and extending therealong. Eachleg 63 of each duct 61 is closed, as by wall s', at its end remote fromsection 64, but in its upper surface is provided wtih a plurality ofports 68 located spacedly lengthwise thereof. The ports 68 of each leg63 of each duct 61 communicate with the interior of an overlying gasflue or combustion chamber 69 so that by said port 68 air is fed intothe related gas flue 69 throughout substantially the length thereof asdistinguished from the single air providing source 49 as describedhereinabove. Each liue 69 is closed at one of its ends by wall s and atits other end communicates with gas inlet pipe 70 secured within anopening 71 in side wall s and connected at its end beyond said side walls to a gas manifold 72 extending along oven wall s in axially parallelrelationship to air manifold 67 and spacedly thereabove. With thisarrangement it will thus be seen that the air and gas manifolds 67 and72, respectively, are located on the same side of oven A therebydistinguishing from the staggered bank arrangement hereinabovedescribed. Such arrangement is productive of obvious economies inproduction as well as promoting enhancing combustion within flues 34 byfacilitating flame propagation.

As shown in FIG. 9 waste gas flue ducts 73 are located spacedly alongwall s of oven A, that is, on the side opposite manifolds 67, l72 andthereby overcoming the difficulties required with the staggeredarrangement herein above set forth.

It should be understood that changes and modifications in the formation,construction, and arrangement and combination of the several parts ofthe carbonizing oven lmay be made and substituted for these herein shownand described without departing from the nature land iprinciple of myinvention.

Having thus described my invention, what I claim and desire to obtain byLetters Patent is:

1. A carbonizing oven comprising means defining upper and lowerelongated chambers, said upper chamber having -a floor formed ofmaterial having heat transfer properties, means for charging rawmaterial upon said upper cham- -ber floor, means for moving said rawmaterial directly upon, and along, said floor, a source of heat providedbelow said floor for transfer therethrough to effect carbonizing of thesaid raw material, said source of heat comprising a plurality of airducts extending transversely of said oven, means defining a plurality ofcombustion flues above said air ducts, la source of gas, meansconnecting said source of gas to said combustion flues, a source of air,means connecting said source of air with said air ducts, each air ductbeing of U-shaped formation having first and second axially parallellegs extending transversely of said oven, there being a short connectingsection extending longitudinally of said oven, said second leg having aplurality of openings for commuication with the overlying combustionflue.

2. A carbonizing oven as defined in claim 1 and further characterized bygas purifying means located exteriorly of said oven, and meansconnecting the interior of said upper chamber and said gas purifyingmeans, and gas pres sure regulating means to maintain a `balancedpressure within the carbonizing oven by regulators which control theoperation of the gas exhauster.

3. A carbonizing oven as defined in claim 1 and further characterized bysaid combustion flues being in axially parallel relationship with saidair ducts and the number of said combustion flues corresponding innumber to said air ducts.

4. A carbonizing oven as defined in claim 3 and further characterized bysaid means connecting said source of gas to said combustion fluescomprising means defining a gas inlet opening into each of saidcombustion ues at one end thereof, means defining 'a gas manifoldconnected to a pre-determined number of said gas inlets, and meansconnecting said manifold to said source of gas, said means connectingsaid source of air t0 said air ducts comprising means defining an airinlet opening into each air duct at one end thereof, air manifold meansin connection with a pre-determined number of said air inlets and meansconnecting said manifold with said source of air.

5. A carbonizing oven as defined in claim 4 and further characterized bysaid air inlets and said gas inlets being located on the same side ofsaid oven, and said means for moving said raw material comprising anendless conveyor for travel through said upper and lower chambers,rotating means provided at opposite ends of said oven about which saidendless conveyor is trained, whereby the upper course of said conveyorwill pass through said upper chamber and the lower course of saidconveyor will pass readily through the lower chamber, means ifor drivingsaid conveyor, said conveyor having a plurality of bar members presentedfor extension transversely of said chambers and being spaced apartlongitudinally of said conveyor, said bar members being disposed forcontactive engagement with the floor of said upper chamber during itstravel therethrough for maintenance of the raw material in heat transferrelationship with respect to said chamber floor.

`6. A carbonizing oven as defined in claim 4 and further characterizedby said air inlets and said gas inlets being located on the same side ofsaid oven, and exhaust ducts located on the other side of said ovenbeing in communication with said combustion fiues for exhaustingexpended gases.

7. A carbonizing oven as defined in claim 1 and further characterized bysaid second leg openings being axially aligned and disposed spacedlylengthwise within said combustion flue for supplying air to saidcombustion flue substantially throughout its length.

References Cited UNITED STATES PATENTS 1,591,023 7/1926 Ditto et al.202-117 XR 1,493,758 5/1924 Lamie 202-117 XR 2,598,931 6/1952 Narsted34-236 XR 2,812,291 11/1957 Hughes 202-101 WILBUR L. BASCOMB, JR.,Primary Examiner D. EDWARDS, Assistant Examiner U.S. Cl. X.R.

